AK UI in 3bet pot

[MATT111]

Villain is TAG. He usually plays higher stakes so I don`t have that many hands on him. He`s 20/16/3 over about 100 hands. This is the third time I 3b him in the last 20 hands. None of the hands were shown down.
Is he taking me to valuetown here always? I figure his preflop calling range is rather liberal given stacks/history/position.

3/6NL
900$ eff stacks

1 limper - Villain raises to 27 - I RR AKo oo SB to 100 - villain calls.

Flop:

655r

I check - villain bets 150 - I call

Turn:

9 (completing r)

checks through

River:

3

Villain bets 300 into 500